ASTM E1252 General Techniques for Obtaining Infrared Spectra for Qualitative Analysis
Lubricants are often complex mixtures containing many different types of molecules. During use, this mixture may change: degradation products may be produced, additives may be consumed and contamination with fuel, water, glycols and other substances may occur. FTIR (Fourier Transform Infrared) Spectroscopy is an excellent method to qualitatively determine changes in lubricants. It is rapid, requires a small sample size and allows two samples to be compared by overlaying the spectra. This method may also be used to determine organic functional groups in samples.
The sample is prepared, and analyzed by FTIR. Reported is the spectra with wave numbers assigned to appropriate peaks.